By my reading of all the current "performance literature" I think all people care about is count(*) w/no predicates and only in the direct path with full scan. I could be wrong about that though. From: Tim Gorman <tim@xxxxxxxxx> To: ORACLE-L <oracle-l@xxxxxxxxxxxxx> Sent: Thursday, February 12, 2015 1:17 PM Subject: Re: HASH Partitioning question C'mon, you need to give us more than that, please? Query for one row? Query for 10 million rows? Aggregating? Not aggregating? Exadata or laptop or something in between? Oracle7? Oracle8i? Windows? Linux? Android? On 2/12/15 13:55, Deepak Sharma (Redacted sender sharmakdeep_oracle@xxxxxxxxx for DMARC) wrote: Is it true that if a table (say 1 billion rows) is HASH Partitioned, then the most efficient way to query it needs to use Oracle parallel threads ?